/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.sdk.extensions.sql.impl.rule;



import com.bff.gaia.unified.sdk.extensions.sql.impl.rel.UnifiedAggregationRel;

import com.bff.gaia.unified.sdk.extensions.sql.impl.rel.UnifiedLogicalConvention;

import org.apache.calcite.plan.RelOptRule;

import org.apache.calcite.plan.RelOptRuleCall;

import org.apache.calcite.rel.RelNode;

import org.apache.calcite.rel.core.Aggregate;

import org.apache.calcite.rel.core.RelFactories;

import org.apache.calcite.rel.core.TableScan;

import org.apache.calcite.tools.RelBuilderFactory;



/**

 * Aggregation rule that doesn't include projection.

 *

 * <p>Doesn't support windowing, as we extract window information from projection node.

 *

 * <p>{@link UnifiedAggregationRule} supports projection and windowing.

 */

public class UnifiedBasicAggregationRule extends RelOptRule {

  public static final UnifiedBasicAggregationRule INSTANCE =

      new UnifiedBasicAggregationRule(Aggregate.class, RelFactories.LOGICAL_BUILDER);



  public UnifiedBasicAggregationRule(

	  Class<? extends Aggregate> aggregateClass, RelBuilderFactory relBuilderFactory) {

    super(operand(aggregateClass, operand(TableScan.class, any())), relBuilderFactory, null);

  }



  @Override

  public void onMatch(RelOptRuleCall call) {

    Aggregate aggregate = call.rel(0);

    TableScan tableScan = call.rel(1);



    RelNode newTableScan = tableScan.copy(tableScan.getTraitSet(), tableScan.getInputs());



    call.transformTo(

        new UnifiedAggregationRel(

            aggregate.getCluster(),

            aggregate.getTraitSet().replace(UnifiedLogicalConvention.INSTANCE),

            convert(

                newTableScan, newTableScan.getTraitSet().replace(UnifiedLogicalConvention.INSTANCE)),

            aggregate.indicator,

            aggregate.getGroupSet(),

            aggregate.getGroupSets(),

            aggregate.getAggCallList(),

            null,

            -1));

  }

}